While democrats are still reeling from the shocking outcome of the US presidential elections, some experts are questioning whether Trump actually won fair and square.

Their concerns focus on the fact that the majority of votes cast this year relied on computer systems which could have fallen prey to malicious actors or have been miscalibrated, and the conclusion of the National Security Agency that Russia was behind the DNC email hack, as well as attacks on US voter registration databases.

CNN reports that a group of scientists and election lawyers are urging the Clinton campaign to call for a recount in three swing states that Trump won. The group includes J. Alex Halderman, the director of the University of Michigan Center for Computer Security and Society, and voting rights attorney John Bonifaz.

According to them, Clinton received 7 percent fewer votes in counties that relied on electronic voting machines, and there’s a chance that they could’ve been hacked. And while they acknowledged that they had not found any evidence of tampering, they noted that the pattern needs to be examined by an independent reviewer.

They’re not alone: In an op-ed on USA Today, UC Berkeley statistician Philip Stark and MIT cryptographer Ron Rivest, both of whom are advisors on the US Election Assistance Commission, suggested what’s called a risk-limiting audit.

It’s essentially an examination of “a random sample of the ballots in a way that has a large chance of detecting and correcting incorrect results.” The idea here is to determine whether a full recount is necessary, by looking at a small fraction of the ballots, and doing so in stages.

The duo explained that auditing about 1.5 million ballots – just over 1 percent of all ballots cast in this election – with just a pen, paper and simple arithmetic could give 95 percent confidence that the results are correct in every state.

The Electoral College is to finalize the results of the election on December 19, and states have until December 13 to submit their counts to the Electoral College.

It’ll be interesting to see if the fear of electronic tampering pushes the US into recounting votes from this election. If you believe the audit is necessary, you can sign the petition put forth by the Verified Voting Foundation on this page.